1. Technical Field
The present invention relates to a printed circuit board and a method of manufacturing the same.
2. Description of the Related Art
Generally, printed circuit boards (PCBs) are manufactured by patterning one or both sides of a substrate, composed of various thermosetting resins, using copper foil, and disposing and fixing ICs or electronic parts on the substrate to form an electric circuit and then coating the substrate with an insulator.
Recently, electronic products have been rapidly multi-functionalized and operated at high speed. In order to keep up with this trend, semiconductor chips, and semiconductor-embedded printed circuit boards in which semiconductor chips are connected with a main substrate have made rapid progress, too.
Therefore, printed circuit boards are required to be highly-densified and be operated at high speed. In order to meet this requirement, printed circuit boards must be light, thin, short and small, be provided with microcircuits, have excellent electrical properties, have high reliability and have a high-speed signal transmission structure.
Meanwhile, as printed circuit boards are used in various fields because of the progress of electronic products, efforts to simplify a process of manufacturing a printed circuit board and reduce the production cost of a printed circuit board are being made.
FIG. 1 is a flowchart showing a conventional method of manufacturing a printed circuit board, and FIGS. 2 to 8 are sectional views showing a conventional method of manufacturing a printed circuit board. Hereinafter, the conventional method of manufacturing a printed circuit board 10 will be described with reference to FIGS. 1 to 8.
First, as shown in FIGS. 1 and 2, a substrate 11 including a first metal layer 12 formed thereon is provided, and then reference holes are formed in the substrate 11 (S10). Then, pretreatment, such as washing, roughening or the like, is conducted.
Subsequently, as shown in FIGS. 1 and 3, a dry film 13 is formed on the pretreated first metal layer 12 (S30).
Subsequently, as shown in FIGS. 1 and 4, the dry film 13 is exposed (S40), and is then developed (S50).
Subsequently, as shown in FIGS. 1 and 5, the first metal layer 12 is etched to form a first circuit layer 14 (S60).
Subsequently, as shown in FIGS. 1 and 6, the dry film 13 is removed (S70). In this case, whether or not the first circuit layer 14 operates normally may be checked.
Subsequently, as shown in FIGS. 1 and 7, the exposed first circuit layer 14 is black-oxidized. (S80).
Subsequently, as shown in FIGS. 1 and 8, the black-oxidized first circuit layer 14 is laminated with an insulation layer 15, and then a second metal layer 16 for forming an additional circuit layer is formed on the insulation layer 15 (S90).
However, the conventional method of manufacturing the printed circuit board 10 is problematic in that process time and cost are increased because its processes, such as exposing, developing, removing, laminating and the like, are complicated.